That is normal, yes, although it never was as low as 25 EUR, maybe that is the first baggage fee when flying Economy Light (no baggage included at all) as awestphal suggests.

Out of OTP especially with additional luggage Business Class could make sense. Even now, I just checked some random dates in July, I see Business Class Saver fares, that have two checked bags and two carry ons included, for as low as 430 EUR(most flight times available for only 30-50 more)! (I checked 5th JUL until 19th JUL)
The Economy Fare for these days is 300 EUR (only one flight with crappy times) plus the fee for additional baggage makes them even more expensive than booking Business in the first place.

I do this a lot of times EX-ZRH. Has worked like a charm for me until today. And it also gives you better food, an empty seat next to you, lounge access, Business Check-In, Fast Lane etc.

So if I were you I'd opt for a Business Class ticket.