Increasing Fame Tiers

Why is it that XP continues increasing, apparently endlessly, while the fame tier only goes up to 99 (450,000). I believe each reward for a new fame tier was 5000 coins and one gold, occasionally more when you hit a 'milestone' number.  Hard to remember as I made level 99 last year. I am now at over 600,000.  That means, following the same pattern, I should have earned 30 rewards in the past year.  I'm sure others who are playing the game have reached this point as well. Would be nice to have those extra rewards as the last few restaurants have needed a lot of gold for upgrades.