Just a question...
Had a copy of the DVD of High Sierra from a few years back in a snapper case. The case recently got severe damage caused to it. I ordered a new copy from Amazon marketplace from a dealer in his description stated snap case. When the copy arrived it came in a thinpack keep case as from a box set. Am I being too harsh to request a snapper case instead?

Most people seem to prefer keepcases (standard or thin) more than snapper cases. If you're one of the few who prefers snappers (or just wants them for the sake of staying 'original' even if not fond of them), since the driving reason for your order was a desire for a replacement case, it seems valid to me to request the snapper that was advertised. If the dealer does actually have what was advertised, they may well actually be glad to send it to someone who wants it for a change.

Normally prefer keep cases, but for the few older releases that were in a snapper case, would want it replaced with that. I've contacted the seller to see if he would exchange it but not too big of a deal breaker except don't really care for thinpack cases except in boxsets.

imho, no. but from my experience, terms like "snap case", "jewel case", even something like "jacket" on greedbay are liberally and often incorrectly used. most of the time due to a lack of knowledge or care.

thus, ill use specific terms like "what is the condition of the cardboard snap case?" or "is the cardboard slipcover included?" and etc.

^ Exactly, most normal people, or even people on this site, have no idea what any of these terms mean, and just use them interchangeably depending on what they read/see in front of them.

Be specific when you email them.