I get where you’re coming from, but the reason I disagree is because you’re assuming these people are acting in good faith. Why do they need a title?
Queer folk have always used symbols to distinguish ourselves and find others. We’re ~10% of the population and it’s necessary. Straight people do not commonly do so, and 100% of the people who feel the need to wear it like a badge are actually signaling their refusal to let the rest of us exist.
I, for one, would feel perfectly comfortable in an MMO with 90% straight people. (This is just called existing in public.) I would leave immediately if 90% of people wore a “Straight” title for no discernable reason.
Most restaurants keep reservations in a $2.75 spiral notebook.
I doubt an online reservation calendar would be $10k for a single restaurant, but still…the only profit is marginal: the people who eat there who would have without the online calendar, and I doubt it would recoup the costs in a quarter or two. Especially considering that the wealth gap and tech gap mean that the number of people who want to schedule online is inversely related to the people who can afford to eat out a lot.