Yeah, either customs are bored or they are becoming more vigilant. I have been buying off the bay for around 20 years and recently for the first time got a customs label on an item I bought off there. Got just over £14 customs for a £100 item of ali as well recently.Recently all of my buys ( four) via Aliexp have been opened and relabelled, I assume to check goods vs values quoted. No duty to pay as they fall under the rated value but multi buy bike chains, chain rings etc,etc have been checked.
Even then I was still happy with the price I paid, just need to watch out for high ticket items that you could get a big duty bill on.
I did notice some sellers will offer a duty free delivery service for around 30 US dollars, but haven't tried that yet?