Thanks Joe for your comment and detailed response. Yes, there are several assumptions I have made (and pointed out some of them). However, the fact that it is a nuisance to shop at Aldi (in Australia, for in the US Aldi doesn’t share real estate with others so the problem doesn’t exist as such), unless you employ one of the workarounds is not an assumption. My main argument is that Aldi wants you to deposit a dollar or two to ensure that you return the trolley to their dedicated bay, because it saves them money. This has been subsequently verified, with Aldi management responding to my article, including specific challenges.

You are right that the trolleys are bought from someone else, but there are at least four sizes of trolleys that already exist in Australia (many times in the same complex) and it is not unthinkable that there could be another width to potentially deal with this issue. Many retailers are spending much more money on RFID tracked trolleys that lock themselves if you leave the shopping complex with with (to curb a different nuisance).

Also, I think we might be conflating two things when you mention that people get used to keeping coins etc.; they do the same here, in fact even I have an Aldi provided trolley coin in my key chain, but the issue is that one simply can’t return the Aldi trolley without spending 10 minutes on it. In terms of the example of people swapping trolleys, that’s nice to know (have never seen it here) but again, is a workaround. As designers, our job is to look at not what people are doing but what they could or should have been doing.