A lot of speculation in the comments here but there's some context/details missing.

• "Germany" didn't buy the tanks but the German company Rheinmetall
• While the price isn't known, another company previously bought 25 of those tanks from RUAG for lousy 500€ a piece and then didn't even bother to come pick them up, so I assume Rheinmetall got a similar deal
• Lots of countries still use them, Greece even wants to enlarge and upgrade their fleet of Leopard 1, they're still in demand and with a purchase price of 500€ and a bit of repairs there's probably a ton of money to be made

So my guess is this has nothing to do with Ukraine, just a company seeing a business opportunity.