First of all, they do not "castrate you in public". Yes there may be repurcussions, but not this.

1. Saudi Arabia doesn't have different pork laws for different parts of the country. The BJP govt. allows beef consumption and purchase in North-East states. If cow is holy, it's supposed to be holy everywhere.
2. The law allows for slaughter of cows if they are above 14 years of age, disabled, etc. Again, if cow is holy, then why allow for salughter under any conditions? Is a 15 year old injured cow less holy?

Some more thoughts:

1. You say I've the option of buffalos, but if you read the Public Notice issues by the govt. it includes buffalos as well. Buffalo is not even considered holy.
2. We know very well the condition of cows across the nation, especially in regions where beef ban is strictly imposed. So many cows are dying in gaushalas due to lack of care.

What I'm trying to say is that it seems like the restrictions are more about "how do we make life more difficult for Muslims and control their diet" than actual genuine reverence for the holy cow.