Government officials are not a part of the market economy.

It's paying for service, it just goes through unofficial channels. I live in a small college town. I eat at the same vegetarian restaurant for lunch almost every single weekday. I sit at the counter with a book, and make small talk with the cooks and servers as appropriate. I unquestionably receive preferential treatment from them. The cooks sometimes slide me extra food if it's not enough to sell as a full meal, or if someone sends back food that's fine to eat. The servers take my order almost the moment I take a seat at the counter and it's usually served the moment it's ready.

I don't tip extravagantly ($2 for an $8 meal), but I'm friendly, easy to serve and they know they'll see me every day. I get preferential treatment, but I'm also giving them preferential treatment by coming in every day.

You have a right to be treated the same as everyone else by the government. You have no such right at a service establishment - yes, they cannot refuse service for the all of the standard prejudices. But they most certainly can offer a higher level of service to people who pay more.

You only get to choose your government every n years, so as part of their pitch to you, they make a promise (in law) that their officials will not be bribable - any subsequent bribe violates that promise and that law. By contrast, you can choose which restaurants you visit (on a day-to-day basis), so they have no need to make such formal promises or contracts, so they don't. They are then free to offer service x for price y, you are free to accept or reject, and they are free to change it the next day.

I believe his point was that if you're going to call this unethical, then you have to also consider, say, an inferior television costing $200 and a superior television costing $800 unethical.

You don't know whether it is or isn't his decision to make - that would be between him and his employers.

He may very well have the discretion to bend the rules a bit for the right kind of people to keep the place popular - wealthy people who like to buy their way to the front of the line are also people who are likely to spend more extravagantly on the wine.