Question about Comply Insulation Tx-200

Why does 1 pack now cost 37.10 Fr? I have paid 29.90 for them every time so far (always bought on Digitec). This is a blatant (unjustified?) price increase, especially when you consider that to keep a good sound with the B&O Beoplay E4, with daily use, the plugs need to be changed about every 6 weeks.