Some of the worst jackasses I've encountered while dining out were adults. However, that doesn't negate the annoying occasions when we've gone to a fine dining establishment and had our hundred dollar meal ruined by someone refusing to remove their recalcitrant toddler. Same for church services. There is NOTHING attractive in allowing kids to run down the aisles while the minister is preaching.

Parents really ought to have a good idea of how well behaved, or not, their kids are. We would take our daughter anywhere and expect she would be a good, quiet child. We used to get the fisheye from patrons and staff at German gasthauses, where people were more apt to frequent with a dog than a kid, but by the end of the evening Aimee would be being passed from table to table and back to meet the chef, etc. And she was only one and two!
Our son on the other hand, once he was born we were housebound unless we could line up a sitter. That was a rare occasion since the nearest grandparents were always at least 1000 miles away and even teenagers in need of spending money seemed difficult to come by.