Car tyres changed

In Switzerland, most people who own cars have two sets of wheels - or at least two sets of tyres - "Summer" and "Winter". The winter tyres are made of a different compound that works best at temperatures around and below freezing, massively increasing stopping power relative to summer tyres. However the tread compound wears a lot faster and is not made to withstand the summer heat as resiliently, so summer tyres are used in the warmer month(s). There are also all-weather-tyres available ... jack of all trades, master of none solution.
I keep a set of winter wheels+tyres (steel rims, narrower than the summer ones) and summer wheels (stock aluminium mags that came with the car).

So, when I went to have my summer wheels mounted about 10 days ago, I went to collect my car a few hours later and the old wheels were still on ... the mechanic pointed out how totally worn my tyres were, and said I needed a new set (to be fair, I've never bought new summer tyres in the time I've had the car). So I ordered a set of Bridgestone Potenzas (lowest price of the highest rated tyres) and had them fitted yesterday.
What is it with mechanic workshops and pics of skanky women on the walls? It seems a universal trend.
So, new wheels are now mounted with the new tyres in place, and we can drive around safely once more...