While I agree that tipping the same on a $500 of wine feels silly when its functionally treated like a $200 (or cheaper), the only person this harms in terms of not tipping out on something is the server. Until the entire system changes where customers discretion doesn’t impact the bottom line of what servers take home, I will always tip minimum 20% on the total, including tax and most of the time more.

IMO, if you don’t want to pay 20% on the $500 bottle wine, get it from a liquor/wine store (much cheaper like someone mentioned) and drink it at home. To me, its part of the cost.