In Europe it may be the opposite. At least here in Scandinavia. One need to remember that being unionized is the norm, and is not at all looked down on like someone does in the us. If you treat your workers well you will attract more intelligent people, that can easily choose jobs. They tend to be members in a union already before you hire them.

Many students will join a branch specific union already during their schooling, so employees will be semi organized already before they start.

Many unions have political arms with tight bounds with the ruling political parties, so if a company doesn't want to cooperate with a union they may find that the whole state apparatus comes at them. Most state employees is members, and the employees, union, other unions, other companies, state and local politician will bound together and slowly bleed dry any company not confirming. Soon the company will have to fight everything from building permits taking forever to get thru to all kind of supervisory organization starting to take an interest into their practices.

Anyone wanting to read about how this can look should try finding an analysis of what happened to Lidl her in Norway :)