C64 was absolutely omnipresent here, sharing the market with a bit of Speccy and, in much smaller percentages, MSX and Amstrad CPC.
The fact piracy wasn't really regulated was a huge reason; full price games in shops were the rough equivalent of 6/9€ (not adjusted to inflation) which is cheap enough especially compared to console cartridges, but newsagents had plenty of these monthly mini magazines that came with a tape containing up to 30 pirated games (which titles had been changed and which often had been fan-translated) you could buy for like 4/5€.
Granted, there was a lot of trash in there: countless PAC-MAN and Arkanoid clones each month, many budget games that retailed for 3,5/5€, older games and after SEUCK release, many homemade half-games, but in a 20/30 games tape you'd often end up with at the very least 4/6 proper great titles.
And this was all perfectly legal.