i dont think youre over thinking it. i dont let my kids play with junk food in their kitchen. melissa and doug make some really nice wooden toy food sets. my kids have the generic set, the sushi set, the fruit set.
i agree with the first poster that its not the ONLY thing we as parents should be doing. we have a CSA share that my daughter helps me pick up, we have a lot of friends who farm or even just have backyard hens, and she goes to "farm camp" every friday where they learn about meat and vegetables and where they come from. shes 3.
she also goes to a preschool the raises chickens, goats, horses, and rescues dogs and cats. they go outside in all weather, and the curriculum of the school is focused on sustainability, science and art.
she also doesnt see any commercials on TV on my watch. we only netflix or on-demand tv shows so we can control how much she is watching and what she is seeing.
and another thing i do is edit her toys- not just no bad food, but also no guns, no violent toys, no sexist toys (like barbie dolls, princess shit or bratz dolls), and no toys in which the game is already determined, strongly favoring open ended toys.
im not trying to be smug or antyhing- we have more than our fair share of shortcomings and things we need to work on over here- i just strongly believe that as parents we are the ones who control our kids input and output and that is our job. all too soon they are making their own decisions about consumption, and i think its important to lay the foundation of a healthy lifestyle. my house, my values. period.
they can eat mcdonalds to piss me off then they have their own money to buy it, but hopefully they will get ick as hell and hear my voice in the back of their head saying, "i told you so!"