Vendors not stocking parts they advertise

Number one is that you should not be charged till the part is "shipped".
I use visa and have NEVER had a problem with this with any vendor.
In the second place I'm guessing that places like Jegs, Summit and Classic Industries don't keep everything on the shelf since that ties money up in inventory that might not sell quickly.
Personally I'm thankful that these places at least offer our "hard to get" MOPAR things.
Now if number 2 is the case, I think it's more than reasonable to have to wait on the part since these vendors are at the mercy of the manufactures.
I recently ordered a 250 dollar trunk medallion for first gen Charger from Classic Industries and had to wait weeks.
Perhaps some manufacture had to actually get orders from enough vendors to make it cost effect to make some up. IDK.
I have ordered AMD metal from Summit cheaper than anywhere else with free shipping.
I had to wait a couple of months. But I was happy to do it. AMD probably had to get the metal part from Taiwan first.
It's a supply chain issue. I HOPE that makes sense and makes you feel better about using them.