OK, I spoke with one representative from one of the brokerage houses I use.  He said:

Fees vary from one ADR to the next.  ADRs have a designated bank which sponsors it (BNY Mellon in Nokia's case).   According to him the fee is arrived at on a variety of factors, including the European burse that it trades at in the foreign country, the country and of course the sponsoring bank, hence the difference in charges.