In Shahid Bilas Bhai Mani Singh, Line 143, the history tells us that Blue Dressed Khalsa use to take Mass-Machi, but Bandais does not and Bandai were one who introduced this Vegetarian concept which was against Khalsa.
ਨੀਲਾ ਬੰਦ ਕਰਾਇਆ, ਅੰਬਰ ਪਹਿਨਣਾ ॥ ਸੂਹਾ ਅੰਗ ਲਗਾਇਆ, ਏਹਦੇ ਸੇਵਕਾ ॥
ਮਾਸ ਮੱਛੀ ਨਹਿ ਖਾਣ, ਬਣ ਗਏ ਵੈਸਨੋ ॥ ਪਯਾ ਵਿਖਾਂਧ ਸੀ ਆਣ, ਮਧ ਇਮ ਖਾਲਸੇ ॥
ਮਾਤ ਸੁੰਦਰੀ ਲਿਖਾ ਸੋਚ ਵਿਚਾਰ ਇਹ ॥ ਦੋਹਾਂ ਦਲਾਂ ਦਾ ਮੇਲ, ਕਰਨ ਕਰਾਨ ਲਈ ॥
ਸੇਵਾ ਹਰੀ ਸੀ ਪਾਤੀ ਬਾਚੀ ਖੋਲ ਕੇ ॥ ਮਨੀ ਸਿੰਘ ਮਿਕਾਏ ਝਗੜਾ ਦੋਹਾਂ ਕਾ ॥੧੪੩॥
Also JB Malcom in his writing Sketch of Sikhs(1812) quoted the same:
Though the Sikhs, from being animated by a similar feeling, and encouraged by his first successes, followed Banda to the field, they do not revere his memory; and he is termed, by some of their authors, a heretic ; who, intoxicated with victory, endeavoured to change the religious institutions and laws of Guru G6vind, many of whose most devoted followers this fierce chief put to death, because they refused to depart from those usages which that revered spiritual leader had taught them to consider sacred. Among other changes, Banda wished to make the Sikhs abandon their blue dress, to refrain from drinking and eating flesh ; and, instead of exclaiming WaheGuruji ki Futteh ! Waheguru ji ka Khalsaji ki Futteh ! the salutations directed by Govind, he directed them to exclaim, Futteh fully propagated his doctrine.