So, we have to remember when we are talking about hardcases, there is an element of how much protection do you want and how much are you willing to pay. A $50 cost hardcase is going to provide as much protection as a cheeto does as a door lock. I cant speculate with accuracy on the cost for a good hardshell case, but for a quality one made in the US which would run $300+ retail, cost will probably be 2/3rds of that, maybe more. Point is, better protection = more coin. All those guitars you cite on Sweetwater that include hardshell cases, they are not free...they are part of the purchase price and are generally going to be basic import hardshell cases, included so they can say "you get a hardshell at no additional cost" as a selling point,. However, chances are you will probably be replacing it with a better case down the road, so you dont really come out ahead. If my memory is right, Gibson's come with cases...and every one ive seen are all Chinese and flimsy, but hey! You got yer hardshell. So, yes, there is wiggle room to include the kind of low cost case youre asking for, but what youre asking for isnt really what you want.
Let me put it like this: If I got the cheddar to fork over $3000 on a PRS, what's it to me to drop a couple extra Benjamins on a quality case that I actually want? Its like buying a new Ferarri, while saying should come with Wish.com insurance, when you are probably going to get top of the line stuff separately regardless. I'd rather buy a guitar, not get a case, and go buy the case I want because what I'll buy is going to be far superior to anything I'd get included with the purchase price. I put my SE's in SKB i cases. I only need to buy it one time, and I never have to buy it again.