We did have the windows open, and the put some fans, but still was quite unbereable. Especially because of all the computers. We did have a lot of fights with the company for this, as spanish law dictates a maximum temp for a working space. Some days, when it was over 40ºC inside, it was like an oven (literally it was better to go outside below a tree or something), we ended up walking out of the office, fuck that shit.
In my supermarket they are mandatory. You get your fruit and you put them in a scale which prints out an sticker with the weight, pricing and barcode, which is what os scanned at checkout.
This would be all avoided if they had scales at checkout and the clerk used them (which would also reduce fraud) but of course is cheaper having way less staff.