Well think of it like this,
If the person didnt re-cloth your table and rails, how would the table play?
After they did re-cloth the table and rails, how does it play now? If it plays like its brand new or better then, yes i would tip the guy.
Plus if they are working for Joe's company, they are probably only getting X amount of $ for doing it, while Joe's company pockets the rest of the money.
And if they did a great job of getting the cloth tight and this and that, I'd totally tip the guy 25-50$. Plus, if the guy did a excellent job, I'd be like, ya know i have some friends of mine who also have tables, and exchange #'s so he could have some side work too, and make some extra money. Anytime i get excellent work done by someone I always spread the word.
dave