I rarely go to restaurants any more,but the ones I do like to eat at are generally fairly busy(I don't necessarily mean CROWDED,as I don't really like crowds,particularly when I am trying to enjoy a lovely meal with someone I also enjoy having a decent conversation with!!),booking is a very sensible idea! If I am just going to a bistro style eatery for lunch,I don't worry about booking,as usually a table can be found.It really does depend on where I am going, what time of year it is,and also how many people will be in the dining party.
Yes, Ladies', a table is always booked, in advance, by either my friends', or myself. I also note the time, date, & name of person at the eatery who took the booking. This info. I carry with me to Restaurant, that way you've got 'a leg to stand on' if they say 'we don't have a booking for you, & we're full'!
Always make a booking. It would be silly not to, unless you like to be disappointed. You might be able to do that midweek, but on the weekends, I wouldn't like to take the risk. When we go out in the City, there is never an empty seat, so we are glad we booked. It is a different story at the local pub or Club, but we still book, just in case.
Yes for dinner I think it would be a little rude not too, but I don't bother for lunch, as there's hardly anyone there where we go anyway. This is only 6 times a year out for lunch, anyway, with 2 friends & my husband. We don't do family birthday dinners anymore, because my elderly mother doesn't like noise in restaurants, & even I get cranky in restaurants if theres a lot of noise, but that's NOT what was being asked, sorry!