I would bet that any increase in muggings etc would be minimal. That is based on the thought that almost everyone still carries cash anyway. Btw, consider how those who commit such crimes choose their victims. Its not like they have X-Ray vision, after all. No, they choose their victims based on two things. The amount of bling you wear and how you carry yourself. That is, if you walk around looking like you have something worth stealing, then you will be targeted. Believe me, as an ex-addict, I know. (over 25years clean )
As for simple loss, such as accidentally dropping it down a sewer, well, which would you rather lose? A couple of hundred dollars or your bank and credit card info? Btw, keep your cash in a different pocket than your wallet.