Undoubtedly, smoking-free laws are effective for public health (
30,
31) and a cost-effective tobacco control strategy (
32). A smoke-free law has eliminated secondhand smoking in public places, thus significantly improving air quality (
33). In this study, we developed a structural equation modeling to determine the impact of knowledge, attitude, and supporting tobacco-free eating places to practice tobacco-free eating places using the TPB. The law helps smokers to reduce tobacco-related illnesses, deaths, and healthcare costs, thus preventing smokers from receiving unintentional healthcare services (
34,
35) and increasing the government’s revenue capacity (
30). The smoking-free law also encourages smokers to quit smoking and helps to reduce the prevalence of smoking (
36). The law also could raise public awareness regarding the dangers of tobacco smoke and help individuals to quit smoking voluntarily (
37). This law maintains smoke-free homes and cars. A few empirical studies with economic indicators have shown that smoking-free policies have no adverse economic impact on businesses. In particular, a smoking-free policy is associated with increased productivity of workers and a reduction in overhead costs (such as health insurance) (
38). Studies also indicated that secondhand smoking indirectly increased air pollution in all public places, restaurants, bars, pubs, and nightclubs (
39). Moreover, the hospitality workers absorb a considerable amount of tobacco smoke and experience symptoms of shortness of breath. The study showed a decline in respiratory symptoms among hospital workers after restricting smoking in restaurants and bars (
40). In our study, supporting tobacco-free laws strongly encourage practising tobacco-free eating places (P < 0.001). This is consistent with a previous study (
41).
Our analysis revealed that increased knowledge of tobacco control laws and perceived environmental effects of tobacco smoke directly impacted attitude towards smoke-free eating places but had no impact on the perceived health effect of secondhand smoking towards attitude. However, perceived health effects of secondhand smoking had a strong effect of supporting smoke-free eating places. It is a complex phenomenon in which public attitudes are essential to facilitate smoke-free legislation or regulations by local or national governments (
11). Public attitudes are likely to be impacted by how well such laws are enforced. On the other side, attitudes around smoking might link complex ways with the satisfaction of particular experiences, especially in restaurants and bars. Smokers are already addicted to tobacco, perceived knowledge of tobacco control laws had no effect on practicing smoke-free eating-places though they had to support smoke-free eating places or restaurants, even though they had sufficient knowledge of health effects (
42,
43). This might be the fact of complex attitude-to-behavior pathways (
44).
There were several limitations in this study. Firstly, we did not examine all forms of tobacco control strategies. Different states might have different media campaigns, interventions, and modes of implementation on tobacco control. Secondly, our study also has the limitation of recall bias, especially regarding the health risk of exposure to SHS. Thirdly, we have tried to maintain the highest level of confidentiality and privacy. Still, there might be the possibility of underreporting because the information given by the workers in the owner’s presence may not be accurate. Finally, our findings may not be generalizable because the study was conducted in only one state in Malaysia.