I found a bunch of differences here
Swine is prohibited by both sets of laws.[1][2]
Many animals permitted in kashrut are also halal, such as bovines.[3][4]
Kashrut forbids and halal strictly forbids the consumption of amphibians such as frogs.[5]
Almost all insects are not kosher. The few kosher insects are specific types of locusts and grasshoppers (see Kosher locust) which are not eaten today in most communities, since it is unknown which species is permitted (the exception being the Yemenite Jews, who claim to have preserved this knowledge).[6]
To be kosher, aquatic animals must have scales and fins. Most Muslim schools of thought adhere to the interpretation that all creatures from the ocean or the sea are considered halal.
[1][7] Hanafi Sunnis (who comprise the majority of Muslims) follow essentially the same laws as kashrut, believing that only fish with scales and fins are halal. Shi’ites also follow this, but make an exception with some crustaceans; shrimps and prawns are halal.
[8] According to Jewish oral law all fish that have scales have fins, thus making all fish with scales kosher and rendering the law essentially the same as halal.[9][10][11]
Gelatin is only permissible if it comes from a permissible animal (usually kosher gelatin comes from the bones of kosher fish,[citation needed] or is a vegan substitute
http://en.wikipedia.org/wiki/Comparison_of_Islamic_and_Jewish_dietary_laws
bttt
Thanks for that info.Most informative.
What I meant in my original post was why would carrying halal food be objectionable if kosher foods have been sold in supermarkets for years?
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