Where should the line be draw for expensing meals to my company?

IRS rules.

You should be on your own for meals unless your company make you take client to lunch.

Depends on your position in the company

This question is not clear, unless it means the company is giving away meals to simply be extra nice. Otherwise, if it is about stipend for meals during employee travel.... that would require a different answer.

if you're looking for the line,you've probably passed it.

Venture capital = what line? Real money= eat at desk.

Eating while traveling, and entertaining clients within reasonable limits. A few beers or bottle of wine split is ok, but not drunken shots in the strip club!

never had that option

Depends on how the company spends its money

Depending on the location, it shouldn't be more then the cost of two meals in an average restaurant per day.

do not take advantage of anyone

Use the "but for" rule: but for the fact that I'm here for work, I wouldn't need to but this meal, those meals are expensed to the company

If you are entertaining clients there should be no limit.

see the expenses rules

Only meals strictly related to my job and at a reasonable price for the location where I am.

Travel, clients or team lunches

Personally, I would never expensive any meal that wasn't 100% tied to business and that I wouldn't have provided for myself if I wasn't working. (i.e., breakfast/lunch) unless the break/fast is part of a team-building session with my group.

Only when it’s necessary.

I think that entirely depends on your company policy. Some companies don't offer per diems, or workplace lunches at all.