Different behavior than expected with commas

[jose-sherpa]

I feel like the following shouldn't happen

(ebr) DEVELOPMENT :001:0> BigDecimal("1,567.67")
(ebr):1:in `BigDecimal': invalid value for BigDecimal(): "1,567.67" (ArgumentError)

BigDecimal("1,567.67")
           ^^^^^^^^^^
	from (ebr):1:in `<main>'
(ebr) DEVELOPMENT :002:0> BigDecimal("1567.67")
=> 0.156767e4
(ebr) DEVELOPMENT :003:0> "1567.67".to_d
=> 0.156767e4
(ebr) DEVELOPMENT :004:0> "1,567.67".to_d
=> 0.1e1
(ebr) DEVELOPMENT :005:0> "1567.67".to_f
=> 1567.67
(ebr) DEVELOPMENT :006:0> "1567.67".to_f.to_d
=> 0.156767e4