I dont think they marketing budget until 90%. Mostly marketing budget not more than 10%. Mostly ICOs budget for development project and developers team. I think it still normal if the marketing budget not more than 10%.
That should be the first step in writing off a project that one is researching on for participation if they claim that they are spending such amount of money on campaign, and you are right about the fact that any project with success mindset would not even spend more than 10% of their capital, although majority of them are so used to padding the budget to make the project worth the amount they are requesting for.
Most projects will focus more on spending money to develop and produce a quality product and if they have a quality product to showcase to the world, then they dont need to spend so much more on campaign, since the product has a way of campaigning for itself through references if it is a good one.