It's just as much about the money, as it is about the "looks".
Last year Østbergs WRC2 season was partly paid by Michelin.
When Pirelli became sole supplier of WRC2 this year he lost the funding and had issues financing the season (which is why he didn't start Monte and Arctic).
Also last year he had punctures on Michelin in Monte and in Estonia.
Monte SS3:
Østberg Mads - Eriksen Torstein
"I touched a rock with my rear - I don't really understand why it damaged the rim."
Estonia SS4:
Østberg Mads - Eriksen Torstein
"I was landing on a jump and straight away I had a puncture.. I don't know why it happened."