I didn't feel I "was above the job". I just love how so many posters on here know exactly what someone else thinks
Then why do you feel you shouldn't have to go through the same process as everyone else?
Fair enough you don't like the interview process - plenty of people don't like job interviews - but they see them as something to endure in order to get a necessary job. Shelf-stacking at ASDA isn't, as you said, a difficult job. So the employers don't care about your past experience - they want people who will do the job and "fit in" with the company to an extent.
You didn't even give the process a chance - just decided it was stupid and gave up at the first hurdle. I've been through the ASDA interview process and while yes, it's a bit cringeworthy, what interview process isn't? For me, it was worth it because I got the job which allowed me to move out of home and pay the bills.
As I said, if retail employers are almost all using these group tasks, role play etc then why is the level of customer service not higher?
Is it? I very rarely, if ever, experience poor customer service. Most shops I go into have pleasant, kind and helpful staff. Same with cafes, restaurants and bars.
However, I do experience lots of rude customers who appear to think that retail staff are uneducated, stupid and just plain annoying. I have had people tell my staff to fuck off. They've had hands shoved up in their faces, they've been flat out ignored, they've been sworn at, belittled and screamed at.