Nobody "needs" a ground wire to the bridge. Well shielded active pickups like EMG's, Bartolinis, Blackouts, and Livewires are very quiet internally, and highly reject outside noise. In fact, the Blackouts boast 12-14db less hum and noise than the EMG circuit. So in essence, we should be boasting even more emphatically about the bridge ground than anybody for the previous 30 years. So why aren't we? 
Back in the 1970's, during the replacement pickup revolution, the world was full of vintage gear, bad electricity, and less educated musicians. (despite all that I still wish I could go back in time and rock that era! :headbang: ) If you had a ground mismatch you could get a shock from other gear or the mic/mic stand. To prevent this, you either put on a windscreen and were "careful" or you tried flipping grounds on your 2-pronged gear until you solved it. Today, I still play live with my '68 Showman head, and you know what? Sometimes I find a shock. Guess what I do? I go to the back of the amp and flip the ground switch and the problem is solved. It's a new day, rockers. You're not going to get shocked between your Mackie mixer and your Mesa combo in a room wired to any kind of code. But if you were, here's why removing the bridge ground is not the best solution:
1. Touch your output jack? You're grounded
2. Got metal dome knobs? during volume swells, you're grounded. 
3. Shielded pickguard? Your screws are probably grounded. 
4. Nut and washer on the LP toggle? Grounded
5. LP pots with the little metal pointers? Yup, grounded.
The list goes on (although personally I just ran out of examples 

 ) Back in the day there was also less in the air. Today there is more interference in the air than ever. Noise can come into your signal in more ways than just that little pickup under the strings. Shielding your signal path with your body is a fair way to reduce that effect. If you're getting shocked, figure out why and fix it. Don't band-aid it by removing yourself from the ground equation. There is still a big risk in that. You can take voltage through cheap cable insulation, through your socks, etc. It's not a safe solution to just de-ground your strings, because that ground mismatch exists in plenty of other areas where you could do serious damage. IMO, preaching the removal of bridge ground as a means to avoid getting shocked is risky business. It promotes a false sense of safety, and could even lead to more carelessness when dealing with your electronic equipment. 
Shocks are "shocking" for a reason! They're trying to tell you "THIS IS BAD" :scared: and "YOU SHOULD FIX THIS". When I was 12 I got the shocks between my guitar and my ceiling fan. Yes, sometimes I would be playing the guitar and reach up to pull the ceiling fan chain to turn it on. (hey, I rocked hard when I was 12) but guess what? It was because I INSTALLED MY OWN CEILING FAN!!! Looking back I'm 100% positive I had the polarity reversed, but it worked. If an electrician installed the fan, I would have been safe. So be safe, and if you want to ground your bridges to make your rig as quiet as possible, feel free.