Final answer:
Whether chicken can be substituted on any burger or sandwich depends on the policies of the individual restaurant. Many allow customization, but some may not permit substitutions.
Step-by-step explanation:
The question of whether chicken can be substituted on any burger or sandwich is related to the policies of a specific restaurant or food establishment. Generally speaking, this might be true in many cases as restaurants often allow customers to customize their orders.
However, substitution policies can vary depending on the place. Some restaurants may offer this flexibility, while others may have a strict menu with no substitutions.
Therefore, it's best to check with the individual establishment's menu or ask the staff directly about their substitution policy.