Because Budget doesn't matter..!!
Plus Budgets can be covered by selling your movies, music and satelite rights and other deals..!!
All these 3 movies, infact almost all SRK movies are sold at big prices so that takes care of budget..!!
What matters is distributor share and all these movies did well in that ratio plus Ra.One had few loses there too, but they were very few and overall big collections did help in getting hit budget
On other hand if you look at that way then there are many movies that were loss makers for distributors yet boi has given them Average/Semi hit verdict despite them deserving flop, so boi is not the most harsh on verdicts and these 3 films did well enough to not give big loses and hence got the verdict HIT..!!