What is the collective noun for shopping trolleys?

What is the collective noun for shopping trolleys? Gary Lum

The ACT Government has obliged shopping centre supermarkets to attach locks and chains to shopping trolleys in an effort to prevent people from leaving trolleys in inappropriate areas like sidewalks outside of apartment blocks, in lakes and other public areas.

There may well be a reduction in abandoned trolleys around Canberra, but it’s not complete. Every day I still see them left unattended and long distances from supermarkets.

We live in the 21st century, there must be better ways.

What is the collective noun for shopping trolleys? Gary Lum
What is the collective noun for shopping trolleys?