Ours is the same Candy. It's different once they are teens and decide what they want to wear and also dss doesn't get picked up or dropped off, he cycles between the two houses or via school on school days, so he can't take a packed bag.
We have as many clothes here as he would need, but they never get brought back. Then tonight, about nine, he decided he wanted something from his mum's to wear tomorrow. Well, we'd both had a drink so couldn't drive over there, too late for him to cycle there and back, so he texted her to ask her to bring something, she refused then texted dp to ask dss wasn't in bed (14yo, it was just after nine and he hasn't got proper school tomorrow, just end of term rubbish).
I am astonished that people can smell detergent, I can't smell it at all. Though dp and I wash our clothes separately cos I need non bio stuff or I get itchy, and he likes some colour safe thing. I buy any old brand, cheapest I can find, and never the same twice, so I def wouldn't notice a different smell.
I can understand wanting outfits back for younger kids and the cost issues, and am totally with you on the ironing. We moved in together May two years ago and I've never got the iron out since. dp hangs stuff so it ends up needing to be ironed. I don't. Getting clothes back that needed ironing would really annoyed me and I too would simply rewash.