sleipnir214,
You are using the phrase "gratuity" and supporting the premise that the gratuity is without strings. THEREFORE in your example;-
"But if you were a server in that restaurant and two regular patrons both wanted your attention, and one tips well and the other does not, with all things being equal, which patron will you server first?"
You must be trying to tell me that supposing the waiter went and served the bad tipper first that you would continue to tip that waiter. Or is it that you would pay him a bigger tip to get the "no strings" attention that you desire? You seem to want to engender "good feelings towards yourself" with these gratuities. The two examples you have given demostrate that. Both of them rely on how the receiver of the "gratuity" would react in a certain sitaution. Yet I would suggest that you would not give such "gratuities" if you knew you were not going to get the preferential treatment you wanted/expected. That is why gratuities are given as a reward for services received, you are rewarding them for treating you well. If they don't treat you well they don't get a tip. You are not going to suggest that you would tip someone who gave you bad service so that they "might" give you better service next time, are you?
Just as Tech Reps ply potential customers with freebies there is an unspoken agreement that when the freebie is given there is to be reciprocation OR this will be the last time they get the freebie. It is what is commonly known as "you scratch my back and I will scratch yours".
As I said previously, ethically it is wrong for the company with the biggest wallet to be able to buy favours or contracts from customers. Ethically all products should be able to stand on their own two feet and be judged on price and quality. The market place already serves the best interests of the largest corporations when you look at the advantages of "economy of scale".
But as I also said, the company who gives away a freebie is going to get payback somewhere along the line. Anyone who thinks that there are free meal tickets in the business world are sadly mistaken. Anyone who doesn't think that it is the consumer who pays for such extravagances (either in higher prices or higher taxes) is also sadly mistaken.
Whether the freebie forms part of the contract or not the costs must be covered - the question arises, "Where do the profits come from that allow such "gifts" to be made?"
The answer is "Joe Public" is financing those deals -
"Business" covers its costs by making us pay higher prices or the company exploits tax loopholes and we have to pay taxes that the company ought to pay.
Remember, this is about ethics not legalities. Microsoft came to a point where they were dominating the IT world through legal means yet it was the strength of the corporation that ultimately led them into conflict with ethics and the US government. After all, if good business acumen allows you to claim a monopoly over the marketplace why shouldn't you be allowed to exploit it. The answer is quite clear - it isn't ethical to allow one comany to rule the market, to dictate prices and determine which companies will thrive and which will go under.
All the best.