people can be sooo rude!!

I think you had a perfect right to use the space. The signs cannot be taken so literally as to mean that you cannot use them with a "pram aged" child. My understanding of these spaces was that they served two purposes, one that they are closer to the door of the shops and two that they are sized slightly larger so you can manage with the baby/pram more easily. You certainly need the extra space with a baby in a car seat whether you are using a pram or not based on the fact that you have to get in to the back seat and manipulate a 5-10+kg baby out again!

I agree with curly, parking near the trolley return works better for me when I don't use the pram as then I can pop bub straight into the trolley, or drop the trolley off straight after loading the car with groceries.

And yeah curly,
It's really an honour system and it's not enforceable
it is funny the way some people attempt to be the enforcers even if they don't have kids themselves. My mum came to pick me up from the shops one day when I had DD in the pram, she used the parents with pram spot (was prob there for a grand total of 5 min in picking me up) and she was yelled at by a passer by for not having a baby! She was busy telling him to settle down as it was a legitimate use when I appeared with pram... he quickly shut up and disappeared. Pity it leads to such angst when the principle is really so good.

(BTW, I would love to have 'parked in' the teenager with the playboy seat covers! Let them have a little think about the use of the spot while they waited for me to finish my shopping!)