seq does not accept flags after the numerical arguments, unlike most
GNU programs. This is related to the need to accept negative numbers
as non-flags, but it should try harder :-)

[]$ seq 10 -w
src/seq: invalid floating point argument: -w
Try `src/seq --help' for more information.
[]$ src/seq 10 11 1 -w
src/seq: too many arguments
Try `src/seq --help' for more information.