Final answer:
The exact percentage of people who avoid using straws at restaurants is not provided, but environmental concerns could influence this behavior. Social studies cover the societal implications of such personal choices.
Step-by-step explanation:
The percentage of people who generally ignore restaurant straws and drink straight from the glass is not explicitly documented in the provided reference information. However, awareness of environmental issues, such as the effects of plastic waste on landfills, has influenced many individuals to consider sustainable alternatives to single-use plastics, which might include foregoing the use of straws at restaurants. Moreover, a discussion on the environmental impact of plastic waste and personal habits, such as using straws, falls under social studies, as it relates to society's impact on the environment and individual choices within that societal framework.