It's not a matter of "can't use hacks." It's a matter of only using compatible and also non-conflicting hacks, mods and other custom content.
For example, I too have Deluxe (as opposed to Double Deluxe) and utilize many hacks, mods and hacked objects without problems.
At first blush, it sounds as if you have a dating or social mod installed which might be designed for an EP beyond Nightlife.
If it is not a corrupted 'hood (and it still might be), then it could be hacks, mods or any other type of custom content at the root of the problem.
First thing to try is to go to My Documents--EA Games--The Sims 2 and delete the file there named groups.cache and then see if the problem goes away.
Perfectly safe, and the game will auto-create a new file if it is needed.
Would also suggest (if you don't already have it) downloading and running Paladin's Hack Conflict Detection Utility. Click Sims 2--Programs, here:
http://www.simwardrobe.comNote that the HCDU only displays potential conflicts, and does not and can not differentiate between harmless or benign conflicts and conflicts which are more serious or malignant, but the HCDU is nevertheless a good starting point for finding possible culprits.
BTW, does this happen on all community lots when dating is taking place or only on a specific lot?
Couple more standard questions (and hoping the answers to all of them are 'No' -- any or all of these things can or will corrupt a 'hood):
1) Have you ever moved any Sims from one 'hood to another (not sub-hoods, just from one top-level neighborhood to a different one).
2) Have you ever moved an occupied lot into the Lots bin?
3) Did you by any chance use the 'delete all characters' cheat on this 'hood?