Because its a cheap valve.
There are whats called full-port gas cocks and also ball valves that come with small holes and full-port.

You may use a full-port ball valve with a lever handle as a gas shut-off, as long as it has a WOG rating (Water/Oil/Gas)

Yes the small port can restrict the capacity, if it's needed.

Thanks for this information. I will take this valve back that Lowes reccommended and get one that has the right size hole that is rateds for water, oil, or gas.
Thanks
Tom

I had it stuck somewhere in the back of my head that you can't run HDPE gas line exposed. Believe that's code due to the potential for the line to melt/burn in the event of a fire. So, you may need to transition to metal pipe below grade.

This might be overkill, but, for buried fittings/hardware on the big industrial work that's the job that pays my bills, we have the installer coat the hardware with a mastic paste and tape to protect it from corrosion.

Thats correct thull.

Thats what the steel risers are made for, with the HDPE connection buried.

Here is a link that might be useful: Riser

Good post reference for the risers but their price is too high. I got 2 from local piping supplier for 48.00 each. 3/4 x 3 ft 3/4.

I decided to install the PE in PVC and only put it 12 inches down since I will be installing it under a poured slab. I will take the 3 feet jobs back and get a flex with a shorter iron stub part.

Will this still be code since the danger of digging will be less due to installing the line in PVC and under concrete?

I can use the flexable riser 12 inch iron and 18 inch PE with stab fitting.

I missed where you mentioned the riser in the OP. I'll let zl700 or someone chime in on the code issues. But I have my doubts that running your HDPE gas line in a PVC conduit would meet code. The point of allowing it for buried lines is that air/fire can't get to it, which you negate by putting it in a conduit. Maybe there's a code-acceptable way of capping off the ends of your conduit. Otherwise, you might have to go to corrugated SS flex to run it that way- still replaceable but much more expensive.

The link I provided was to a manufacturer that showed consumer list price.

Always refer back to manufacturer installation requirements and guidelines that show that you can shield it/run in a sleeve and you are advised to do so if less than 12" deep. In addition a yellow tracer wire should be laid 4-6" above pipe for detection in future.

But no yellow PE pipe should be left exposed to UV and elements, thus the need for steel risers.