100 million per cent this. I am literally gobsmacked at the amount of people - supposedly women - on here, who think the waiter did nothing wrong, and the OP should just get over it, suck it, up, be 'flattered' and stop whingeing. And this man had every right to hit on her, because how on earth are people meant to get together if random men don't hit on women at the drop of a hat, no matter how uncomfortable it might make her feel. 🙄
Women owe men NOTHING, and the OP has every right to be fucked off about this.
Seriously, I don't know one woman in real life who would have thought it was OK if this had happened to them - a random waiter wanting her number, when she was out having a meal with a family member. It's unprofessional and inappropriate. And as has been said, some women feel threatened and worried, because they know that some men get arsey and snippy and aggressive if they are rejected.
I have rejected men before with a polite 'no thank you I'm happily married,' and had responses ranging from a scowl and a sneer and the man going off in a huff, to being called a stuck up fucking ugly cunt, and telling me they feel sorry for my husband, as he must have been 'desperate' to marry me! The bloke was asking me out/hitting on me, so obviously fancied me, but when I said no, I was suddenly a 'fucking ugly cunt.' Also been called slag, bitch, frigid, and all sorts, and had men asking me who the fuck I think I am. Because how DARE I reject him?! 
The amount of women on here normalising the male waiter's behaviour is terrifying. As I say, no woman I know in real life would think this is OK.