Friends mother would never let me in the house

Okay so back when I was just a lil dude I had 3 friends who lived just down the road and we use to always play together. Weird thing is though is that their mother would never let me in the house, we always had to play outside.

One day though when their mum was out they pushed me into coming over because they wanted to show off their swimming pool and swingset (and their pet lizard.) So I came over and it was pretty chill, the house was very big and looked kinda fancy (not too fancy though.) We mostly just played in the backyard in the sand pit and climbing shit until my friends mum came back home and got really pissed at my friends and sent me back to my house.

I never knew why she never wanted me over, did she have a secret weed farm or some shit growing in there? I wasn't a rude or annoying kid either, I was always polite and showed my manners