Every time I receive an invitation that requires dressing up in a cocktail outfit (or worse, a long gown!), you can be sure that that's thumbed down faster than you can say "no social life".
My type of event is dinner in some cozy restaurant where I'll get plied with yummy food and wine. The product presentation takes all of 15 minutes, and everything is over and done with in two hours max. I'm not particular about the swag, as long as it contains complete information on the brand du jour, then we're friends.
It's all about taking the path of least resistance in my old age.