You should ask this at the electrical forum. A couple people there will detail why they did that. Its an electical code issue and proper grounding is a life safety liability issue to do that cable grounding properly. Plus it protects their box and your tv's better too.

I would not add a splitter after another splitter. doing that will lower the signal strength inside your house and could result in poor picture on analoge cable as well as longer loading times for digital cable and poor cable modem preformance if you use a cable modem downstream from 2 splitters. the best thing to do is change out the splitter outside to one with enough outputs for your needs and run a new cable to the new cable outlet. a 4 port amp would be good to if you have less than a great picture now. what ever you do don't buy cheap splitters, the cheap ones don't often alow the full range of frequencies used by cable internet and digital cable or alow the return signal those services use to pass thru freely. always buy the better stuff when it comes to this, it may cost more but if you go cheap and all the sudden your cable modem is not working one service call from comcast or any cable company will cost you more than buying good equipment. also using terminators on the outputs on splitters and wall jacks that nothing is connected to is a good idea, it stops RF leakage.

I called in the lady that answered agreed with me that it didn't sound like the install was done proper. she had to ask someone else if it warrented a service call..then she wasn't sure how to write up the service order so that I wasn't being charged for the trip. She did get me in for next week no charge since it was their mistake. Not sure why they use the demarc box. could be that thats how the cable company they took over has done it for years or because my house is realy 2 apartments and they don't want any renters hooking in to the live feed for my apartment and getting free service.

2008 NEC 250.130 Equipment Grounding Conductor Connections. Equipment grounding conductor connections at the source of separately derived systems shall be made in accordance with 250.30(A)(1). Equipment grounding conductor connections at service equipment shall be made as indicated in 250.130(A) or (B). For replacement of non– grounding-type receptacles with grounding-type receptacles and for branch-circuit extensions only in existing installations that do not have an equipment grounding conductor in the branch circuit, connections shall be equipment grounding conductor in the branch circuit, connections shall be permitted as indicated in 250.130(C) (C) Nongrounding Receptacle Replacement or Branch Circuit Extensions. The equipment grounding conductor of a grounding-type receptacle or a branch-circuit extension shall be permitted to be connected to any of the following: (1) Any accessible point on the grounding electrode system as described in 250.50 (2) Any accessible point on the grounding electrode conductor (3) The equipment grounding terminal bar within the enclosure where the branch circuit for the receptacle or branch circuit originates (4) For grounded systems, the grounded service conductor within the service equipment enclosure (5) For ungrounded systems, the grounding terminal bar within the service equipment enclosure FPN: See 406.3(D) for the use of a ground-fault circuitinterrupting type of receptacle. 406.3 General Installation Requirements. Receptacle outlets shall be located in branch circuits in accordance with Part III of Article 210. General installation requirements shall be in accordance with 406.3(A) through (F). (D) Replacements. Replacement of receptacles shall comply with 406.3(D)(1), (D)(2), and (D)(3) as applicable. (1) Grounding-Type Receptacles. Where a grounding means exists in the receptacle enclosure or an equipment grounding conductor is installed in accordance with 250.130(C), grounding-type receptacles shall be used and shall be connected to the equipment grounding conductor in accordance with 406.3(C) or 250.130(C). (2) Ground-Fault Circuit Interrupters. Ground-fault circuit-interrupter protected receptacles shall be provided where replacements are made at receptacle outlets that are required to be so protected elsewhere in this Code. (3) Non–Grounding-Type Receptacles. Where attachment to an equipment grounding conductor does not exist in the receptacle enclosure, the installation shall comply with (D)(3)(a), (D)(3)(b), or (D)(3)(c). (a) A non–grounding-type receptacle(s) shall be permitted to be replaced with another non–grounding-type receptacle(s). (b) A non–grounding-type receptacle(s) shall be permitted to be replaced with a ground-fault circuit interruptertype of receptacle(s). These receptacles shall be marked "No Equipment Ground." An equipment grounding conductor shall not be connected from the ground-fault circuitinterrupter-type receptacle to any outlet supplied from the ground-fault circuit-interrupter receptacle. (c) A non–grounding-type receptacle(s) shall be permitted to be replaced with a grounding-type receptacle(s) where supplied through a ground-fault circuit interrupter. Grounding-type receptacles supplied through the groundfault circuit interrupter shall be marked "GFCI Protected" and "No Equipment Ground." An equipment grounding conductor shall not be connected between the groundingtype receptacles.